Here are some positive and negative effects of Stalin:
Positive - emergence of middle class, women could do male jobs in the industry, better education which gave Russia their own skilled technicians, positives of collectivisation for peasants was that poorer peasants now got shared profits, food rationing during the five year plan meant everyone would have something to eat.
Negatives - Collectivisation caused many skilled worker to be purged during the "de-kulakisation" of skilled peasants who disagreed with collective farms. They neglected fields which later caused the Great Famine where millions starved. Stalin's harsh policies meant if people did not meet quotas they would be purged which lead workers to lie about how much was being produced - they were not leaving enough for themselves. It also meant long working hours with little food. The purges seriously affected the Army as the most important Generals had been killed meaning the Army was unorganised. Many great composers left Russia by 1917 during the Cult of Personality and emergence of "Socialist Realism". Industrialisation neglected consumer goods which left many shops empty.
So was Stalin a great leader who reformed and modernised Russia?
He brought about both positive and negative reforms, however, it must be said, he did contribute significantly in the modernisation of Russia.
Pretty easy essay question.